Form for concrete construction



G. A. BONELL] FORM FOR CONCRETE CONSTRUCTION Feb. 26, 1924.

Filed April 20, 11.923

Patented Feb. 26, 1924.

MNETE STATEfi GEORGE A. BONELLI, OF KINGMAN, ARIZONA.

FORM FOR CONCRETE CONSTRUCTION.

Application filed April 20, 1923. Serial No. 633,425.

To all whom it may concern:

Be it known that I, GEORGE A. BoNnLLI, a citizen of the United States of America, residing at Kingman, in the county of Mohave and State of Arizona, have invented cert'ain new and useful Improvements in Forms for Concrete Construction, of which the following is a specification, reference being had therein to the accompanying drawing.

My invention relates to improvements in molds and has for its object to provide a mold comprising inner and outer collapsible forms and coiled spiral spacing elements interposed between the inner and outer forms; with means for holding and locking the s'aid inner and outer forms in fixed operative position, and unlocking and collapsing said forms after the plastic material introduced to the mold has set sufficiently to permit the removal of said forms.

Other features of my invention will appear from the appended description.

Drawings.

elevation of a structure Fig. 1 is a side head and outer Description.

The inner form A is made of a single sheet of suitable flexible material having the locking grooves 1 and 5 formed along the length of its longitudinal meeting edges. The distending, locking and collapsing mechanism for the form A is mounted eccentrically within said form, and comprises the arms 6 and 7, fixed to the inner face of the form A as shown and flexibly connected to the disk 8 by the links 9-9; the disk 8 having a suitable aperture 10 to receive a bar 11, the rotation of the bar 11 serving to draw the arms 6 and 7 inwardly, disengaging the locking grooves i and 5 from each other, with resultant diminution of the diameter of the form A to permit its withdrawal from the molded structure.

The outer form B is similarly formed of a single sheet of suitable material whose longitudinal edges are bent outwardly to form the walls 12-12 having outwardly turned flanges 12. A suitable spring cincture 13, formed as shown in Fig. 2 embraces the form B and engages the flanges 12 said cincture 13 having the terminal studs 14-14= held in operative position by the removable annulus 15. v

lnterposed between the forms A and B are coiled-spring spacing and reinforcing members 16, wound spirally around the form A, and arranged parallel to each other as shown. I have illustrated two of the members 16, whose terminals 17 extend through the head 18, which head 18 is apertured to receive them, and also has the aperture 19 to permit the bar 11 to pass, and to be held thereby when the form A is in the distended and operative position shown in Fig. 3.

Mode 0 7 operation.

The parts being assembled 'as shown, the desired plastic material is flowed into the mouth formed by the walls 11-11 to fill the space between the forms A and B. When the material has sufficiently set and hardened to sustain itself in shape, the head 18 is removed. The bar 11 is rot'ated to collapse the form A, which is then withdrawn, leaving the members 16 embedded in the molded structure, their terminals 17 protruding in position to be engaged with like terminals 17 of other members 16 if desired, for the purpose of molding an abutting structure.

The studs 14.14 are released by the removal of the annulus 15, and the cincture 13 is sprung open, permitting the spreading of the form B and its removal from the molded structure.

While I have illustrated the forms A and B as tubular, I have done so only as a matter of simplicity and convenience in illustration, and th invention is capable of use in molding a wide range of hollow structures.

I cl'aim 1. The improvement in molds comprising inner and outer forms and a combined spacing and reinforcing member arranged spirally between said inner and outer forms.

2. The improvement in molds comprising inner and outer forms and spacing means therefor comprising a plurality of parallel reinforcing members spirally wound around said inner form.

3. The improvement in molds comprising inner and outer forms-and a-eombinedspacw therefor -oomprising a pluralityoifparallei 10 ing andireinforoingniember arrangedsspireinforcing,members spirally Wound" around rally between said inner and outer forms-in said inner form, in combination with a combination with a headvformingiaolosure. head forming ..a. closure for the mold and 5 for the mold and apertured to permit a terapertured to permit the terminals of said minal of said spacing and reinforcing mem reinforcing-members to protrude. 15 her to protrude. In testimony whereof I have hereunto 4. The improvement in moldscomprising affixed signature:

inner and outer forms and spacing means GEORGE A. BONELLI. 

